Engineered biosynthesis of medium-chain esters in Escherichia coli
Yi-Shu Tai1, Mingyong Xiong1, Kechun Zhang1
1Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA.
Metabolic Engineering
|December 3, 2014
Summary
This study engineered E. coli to produce isobutyl acetate (IBAc) and isoamyl acetate (IAAc) from glucose. The engineered yeast alcohol acyltransferase ATF1 enabled high-yield biosynthesis of these valuable esters as renewable chemicals.
Area of Science:
- Synthetic biology
- Metabolic engineering
- Industrial biotechnology
Background:
- Medium-chain esters like isobutyl acetate (IBAc) and isoamyl acetate (IAAc) are widely used solvents and fragrance components.
- Current production methods often rely on petrochemical feedstocks, necessitating sustainable alternatives.
Purpose of the Study:
- To develop a sustainable biosynthetic route for IBAc and IAAc production in E. coli.
- To identify and optimize enzymes for efficient ester formation.
- To achieve high-titer production of these esters from renewable resources.
Main Methods:
- Engineering synthetic metabolic pathways in E. coli utilizing native amino acid biosynthesis pathways (valine and leucine).
- Screening alcohol acyltransferases (ATFs) from various organisms for esterification activity.
- Optimizing E. coli strains by deleting byproduct formation pathways (Δldh, ΔpoxB, Δpta).
- Performing scale-up fermentation in a benchtop bioreactor.
Main Results:
- Identified ATF1 from Saccharomyces cerevisiae as the most effective enzyme for IBAc and IAAc synthesis in E. coli.
- Achieved a production of 36 g/L of IBAc after 72 hours of fermentation in a 1.3-L bioreactor.
- Demonstrated significant improvement in ester production through strain engineering and byproduct pathway deletion.
Conclusions:
- Established a feasible method for the total biosynthesis of medium-chain esters from glucose using engineered E. coli.
- Highlighted the potential of ATF1 as a key enzyme for industrial ester production.
- Paved the way for the development of renewable chemical manufacturing processes.
Keywords:
E. coliEsterIsoamyl acetateIsobutyl acetateMetabolic engineeringPathway manipulationRenewable chemicalsMore Related Videos
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